Magnetic elements such as inductors and transformers are widely used in power supply apparatuses or many electronic devices to generate induced magnetic fluxes. A transformer is a device that transfers electric energy from one circuit to another through coils in order to regulate the voltage to a desired range required for powering the electronic device.
Take a switching power supply for example. The power conversion circuit of the switching power supply comprises magnetic elements. The magnetic elements include a transformer and an inductor. The transformer and the inductor are electrically connected with each other. FIG. 1 schematically illustrates a transformer and an inductor mounted on a circuit board according to the prior art. The transformer 10 and the inductor 11 are disposed on the circuit board 1. A terminal 102 of a secondary winding coil 101 of the transformer 10 and a terminal 112 of a conductive wire 111 of the inductor 11 are respectively welded on corresponding bonding pads of the circuit board 1. In addition, the transformer 10 and the inductor 11 are electrically connected with each other through a trace pattern (not shown) of the circuit board 1.
Since the transformer 10 and the inductor 11 are separate components, a lot of space of the circuit board 1 is occupied by the transformer 10 and the inductor 11. Under this circumstance, the layout flexibility of other electronic components is deteriorated, and it is difficult to reduce the overall volume of the electronic device. Moreover, since the transformer 10 and the inductor 11 are electrically connected with each other through a trace pattern of the circuit board 1, the process of mounting the transformer 10 and the inductor 11 is complicated and the power loss is increased. Under this circumstance, the power conversion efficiency of the electronic device is impaired.
Therefore, there is a need of providing an integrated magnetic element in order to obviate the drawbacks encountered in the prior art.